Add contributor arnavsharma990 with interactive Tic-Tac-Toe component

Author: arnavsharma990

src/main/scala/gsoc/contributors/all.scala

@@ -16,6 +16,7 @@ val allContributors = NonEmptyList.of(
   parthmozarkar,
   `scala-steward`,
   `the-ivii`,
+  arnavsharma990,
   `piyush-t24`,
   valencik,
   `zayd-r`,

src/main/scala/gsoc/contributors/arnavsharma990.scala

@@ -0,0 +1,97 @@
+package gsoc
+package contributors
+
+import cats.effect.*
+import fs2.concurrent.*
+import fs2.dom.HtmlElement
+import calico.html.io.{*, given}
+import calico.syntax.*
+
+object TicTacToe:
+  enum Player:
+    case X, O
+    def symbol: String = this match
+      case X => "✕"
+      case O => "○"
+    def next: Player = this match
+      case X => O
+      case O => X
+
+  case class State(
+      board: Vector[Option[Player]],
+      turn: Player,
+      result: Option[String]
+  )
+
+  val fresh: State = State(Vector.fill(9)(None), Player.X, None)
+
+  private val lines: List[(Int, Int, Int)] = List(
+    (0, 1, 2), (3, 4, 5), (6, 7, 8),
+    (0, 3, 6), (1, 4, 7), (2, 5, 8),
+    (0, 4, 8), (2, 4, 6)
+  )
+
+  def checkResult(board: Vector[Option[Player]]): Option[String] =
+    lines
+      .collectFirst {
+        case (a, b, c)
+            if board(a).isDefined && board(a) == board(b) && board(b) == board(c) =>
+          board(a).fold("")(p => s"${p.symbol} wins!")
+      }
+      .orElse(Option.when(board.forall(_.isDefined))("It's a draw!"))
+
+  def isWinningCell(board: Vector[Option[Player]], idx: Int): Boolean =
+    lines.exists { case (a, b, c) =>
+      List(a, b, c).contains(idx) &&
+        board(a).isDefined && board(a) == board(b) && board(b) == board(c)
+    }
+
+val arnavsharma990: Contributor = Contributor("arnavsharma990"):
+  import TicTacToe.*
+
+  SignallingRef[IO].of(fresh).toResource.flatMap { state =>
+    def play(idx: Int): IO[Unit] =
+      state.update { s =>
+        if s.board(idx).isDefined || s.result.isDefined then s
+        else
+          val newBoard = s.board.updated(idx, Some(s.turn))
+          State(newBoard, s.turn.next, checkResult(newBoard))
+      }
+
+    div(
+      p(
+        "I am ",
+        strong("@arnavsharma990"),
+        " on GitHub. I agree to follow the Typelevel Code of Conduct and Typelevel GSoC AI Policy."
+      ),
+      p(b("Tic-Tac-Toe — challenge a friend!")),
+      state
+        .map(s => s.result.getOrElse(s"${s.turn.symbol}'s turn"))
+        .changes
+        .map(msg => p(styleAttr := "font-weight:bold;font-size:1.1em", msg)),
+      div(
+        styleAttr := "display:inline-grid;grid-template-columns:repeat(3,64px);gap:4px;margin:8px 0",
+        (0 until 9).toList.map { idx =>
+          button(
+            styleAttr <-- state.map { s =>
+              val bg =
+                if s.result.isDefined && isWinningCell(s.board, idx) then "#2ecc71"
+                else "#ecf0f1"
+              val clr = s.board(idx) match
+                case Some(Player.X) => "#e74c3c"
+                case Some(Player.O) => "#3498db"
+                case None           => "#333"
+              s"width:64px;height:64px;font-size:1.8em;font-weight:bold;cursor:pointer;background:$bg;color:$clr;border:1px solid #bdc3c7;border-radius:4px;display:flex;align-items:center;justify-content:center"
+            },
+            state.map(s => s.board(idx).fold("")(_.symbol)),
+            onClick --> (_.foreach(_ => play(idx)))
+          )
+        }
+      ),
+      button(
+        styleAttr := "margin-top:8px;padding:6px 18px;font-size:1em;cursor:pointer",
+        onClick --> (_.foreach(_ => state.set(fresh))),
+        "New Game 🔄"
+      )
+    )
+  }